Small leak, narrowing down location

[firedogut]

I’ve found a few issues with my system this year and need a little help on one of them.

I had a valve that was allowing a small amount of water to seep out. I ran the flush on the valve and it fix it. I’m guess small debris above the diaphragm is what caused it.

In another i have another issue I can’t seem to troubleshoot correctly. I had a head that appeared to be seeping water. Open the valve and went ahead and replaced the diaphragm. However if I turn off my valve at the the back flow preventer wait a little while and then turn it back on was briefly sprays from a couple of sprinkler heads. This makes me think that the valve is not closing fully. I’m not sure if this also happened prior to diaphragm replacement.

The water meter shows a 0.08GPM leak someplace in my sprinkler system after the back flow preventer. Doesn’t sound like much but that’s over 3,000 gallons a month.

few questions:

should a zone allow water to flow when you turn on the main water valve or valve at the back flow preventer?

if water is seeping from a head are there other causes besides an issue at the valve? Could a bad solenoid cause this? (Seeping 24/7 not from low head pressure).

zone runes fine via the controller.

 

[Drick]

should a zone allow water to flow when you turn on the main water valve or valve at the back flow preventer?

I'm not an expert, but I have a syetem where the zone valves aren't continuously pressurized. Out of 18 zones I have one that will do this. It is the zone with the highest elevation. Aside from maybe a gallon of water escaping from the heads while the zone vale is being repressurised its never been an issue.

if water is seeping from a head are there other causes besides an issue at the valve? Could a bad solenoid cause this? (Seeping 24/7 not from low head pressure).

If shutting off the water to your irrigation fixes the problem its probably dirt in the valve and you'll likely need to disassemble and clean it. That said it may be worth partially digging up the sprinkler head to confirm where the water is coming from. Last year I thought I had a leaky valve. It turned out to be a crack in the sprinkler housing.

 

[Sponsor]

 

[WorthFlorida]

After the Texas freeze event, it is possible a leak can be anywhere. A PVC pipe can have a crack in it or the glued joint is weeping before any valve or at the valve. At the back flow, shut the water off if possible and look at the meter. Unfortunately, not much you can do but cut the pipe to each valve and add a ball valve so each zone can be completely shut off. Perhaps it is best to replace the diaphragms since they can get hard over time before hacking into everything.

In Florida, this happens quite often from tree and shrubbery roots where they'll wrap around the PVC and lift the pipe, over time a glued joint will be pulled apart. After you see the next water bill do you realized there is a problem. Then look for the thickest and greenest grass since it is getting plenty of water. From the water supply to the irrigation system, if there is a shrub in the pathway, it's a place to start looking.

If you have a hilly lot, the sprinklers at the lowest point will siphon and weep water for that zone for hours sometimes but it shouldn't pull open any valve and hear it at the antiphon. There are sprinklers with built in check valves to prevent this. That is sprinklers at the highest level need the check valves to prevent air from entering.